Water-cooling device for compressors



May 13, 1930. s. B. REDFIELD 1,758,538

WATER COOLING DEVICE FOR COMPRESSORS Filed Dec. 3, 1927 INVENTOR. 9): die/J21: BReyz'dd Patented May 13, 1930 UNHFED stares PATENT OFHFICE SNOWDEN B. REDFIELD, OF EASTON, PENNSYLVANIA, ASSTGNOR T INGERSOLL-RAND COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATIONOF NEW JERSEY a: WATER-COOLING DEVICE FOR COMPRESSOR-S Application filed December 3, 1927. Serial No. 237,445.

This invention relates to compressors, but more particularly to a water cooling device connected to the water jacket of the compressor cylinder and adapted to shut-off the supply of cooling water to thefwater jacket simultaneously with the starting and stopping of the compressor.

It is an object of the invention to prevent the wasteful discharge of cooling water through the water jacket of the compressor while the compressor. is idle. 1

Another object of the invention is to insure an adequate supply of cooling water to the compressor cylinder at the beginning of the loaded period of the compressor. Other objects will be in part obvious and in part pointed out hereinafter and to all of these ends the invention consists of the teatures of construction and arrangement of parts having thegeneral mode of operation substantially as hereinafter described and claimed and illustrated in the accompanying drawing, in which is shown a compressor .cylinder in longitudinal sectional elevation having the invention applied thereto.

Referring more particularly to the drawing, A designates a portion of a double acting compressor-having a cylinder B in which is disposed a pistonC. The piston C is provided with the usual piston rod D which extends,

slidably through a head E on one end of the cylinder and may be connected to a suitable prime mover (not shown) in a wellknown manner. A head F forms a-closure for the opposite end of the cylinder B and in these heads E and F are suitablechambers G which, in conjunction with a chamber H encircling the cylinder-B intermediate its ends, constitute the water jacket for the cylinder.

At opposite ends of the cylinder B are the usual inlet valves J through which the air intended to be compressed may enter thecylinder. At these points of the cylinder also are the discharge valves K through which the compressed air may pass into a discharge chamber L forming apart of the cylinder. The air thus discharged into the chamber L may pass through a discharge opening-O con- ;;nected with a receiver tank P by a pipe Q.

In'the' wall of the cylinder B is an inlet opening R through which the atmospheric air ntended to be compressed may passto the inlet valves J. The inlet opening R in this instance is .controlled by an unloader valve generally designated by S and comprising a hollow casing'T in which are formed ports U and V. The ports U' and V in addition to their function of admitting air into the casing S alsoact as a guide for a valve W which cooperates with the ports U and V for controlling the intake supply to the compressor.

Acting on one end of the valve is a spring X,

which seats with its other endagainsta set screw Y threaded into the casing S for adj usting the tension of said spring 'X. i

In its open position the valve against a cylinder Z which forms an integral part of a cover I) attached to the casing T. In the cylinder Z is disposed a piston 0 against which pressure valve W.

Suitable means are provided for automatically cutting oii the supply oi cooling water from the water jacket of the cylinder B and which cooling water is conveyed to the water jacket through a pipe dcominunicating in this instance with the chamber H. These means consist of a water valve 6 interposed in the pipe d and comprises a casingf in the lower end of which are a pair of chambers g and h divided by a wall 70. A port 0 is formed in the wall is to afi'ord communication between the'chambers g and h. At the lowermost end of the port 0 is a valve seat 10 for a valve 9 reciprocable in the port 0. The valve 9 is of the poppet type and has an upwardly extending stem 1" on which is disposed a piston s slidable in the uppermost end of the cas- In the piston s is a chamber 25 for the reception of a spring M which acts with its uppermost end against the piston and with its lowermost end against a shoulder v inthe casing f for actuating the piston s in an upwardly direction to close the valve q. At the uppermost end of the piston s is formed a tapered surface 10 which cooperates with a correspondingly tapered seat m in the easing 7' to prevent leakage of pressure fluid past the piston into the casing f. A cover y W seats fluid may act for closing theis secured to the top of the casing f and has a chamber 2 into which pressure fluid may be admitted for depressing the piston s and thus open the valve 9.

Pressure fluid for actuating the piston s is conveyed to the chamber a through a pipe 2 connected at one end'to the cover 1/ and with its other end-toapi-pe 3. The pipe 3- may be said to be in the form of a loop and .communicatesat its front and rearward ends with the corresponding ends of the piston C through check valves 4 and 5 respectively. The check valves may be onnected to the usual indicator-holes of' the cylinder B and consist of cup shaped valves 6- reciprocable in'casings 7. Springs 8 disposed between the valvesu6 and covers 95 threaded into the easings Ttend. to m'aintain'th'e said valves in' closed: position.

The valves 6 serve to admit pressure fiuld from the cylinder B into the pipe 3 but are so disposed with respect to the indicator ports of the cylinder that they will not admit air into the cylinder on the suction stroke of the piston C.

Interposed in the pipe 3is a relief valve 10 consisting of a casing 11. In the upperend of V the casing is a passage 12' which forms a connection between thesections of the pipe 3.-

In the passage 12 is a depending annular flange 13 which acts as a guide for a ball valve 14 adapted to control a port 15 in the casin 11. The ball valve 14 is normally held closed by a. spring 16 and controls communication between. the passage 12 and atmospheric ports 17 in the casing 11.

The lower portion of the casing 11 is in the form ofacylinder 18 in which'is disposed a piston 19 normallyl'ield in retracted position by a spring 20 The spring 20- is preferably disposed in the piston 19 and acts with its uppermost end ona wall 21 in the-casing 11. A plunger 22 which may be secured with its lowermost end to thepiston 19 extends with its other end against the ball valve 14.

The admission of pressure fluid into the cylinder 18 for actuating the piston 19'is preferably' effected in synchronism with the stopping of the prime mover or with the unloading of the compressor. The meansfor accomplishing this in the present instance consists of anaauxiliary valve23'of a well known type having; su table valve mechanism for controlling communication between the pipe 24 leading from the auxiliary valve 23 to the receiver tank and a pipe 25 leadingfrom the auxiliary valve to'the relief'val've 10 While, as beforestated, the valve mecha nism of the auxiliary valve 23 is not shown,-

its position is indicated by a stem 26 which projects from the lowermost end of the auxiliary valve=23 and" rests on aleVe'r 27 pivoted on the foot of the auxiliary valve 23. A terminal 28*of the lever 27 may be pivotally connected to an armature 29of an el'ectro-magnet the motor,

30 attached in this instance to the auxiliary valve 23. 31 and 32 designate wires which lead from the electro-magnet 30 to a switch (not shown) whereby the starting and stopping of the prime mover for the compressor may be controlled.

y The pipe 25 leading from the auxiliary valve 23 to the relief valve 10 maybe extended to supply pressure fluid to the cylinder Z of the unloader valve S simultaneously with the.

air drawn into the cylinder B through the.

inlet opening R will be compressed and discharged into the discharge chamber L from whence it may pass through the discharge opening 0 and the pipe into the receiver tank P. At the same time pressure fluid will fio-w through the check val-ves't and 5 and the pipes 3 and 2 into the chamber a of the water g valve 1) and acting against the piston s, will depress said piston'and thus hold the valve gopenf In this position of the valve 9 water may flow through the pipe (Z into the water jacket. Such supply of cooling water may continue uninterruptedly to the water jacket as long as air is being compressed in the cylinder B.

/Vhenever' the starting switch of the motor which drives the compressor'is'opened to stop the electro-magnet 30' will become deenergized. This will enable the armature 29 to drop and automatically open the auxiliary valve 23' in a well known manner to admit pressure fluid from the pipe 24into the pipe 25 and thus to the cylinder Zfor closing he'valve W in order to cut off the intake supply to the cylinder B.

Upon the admission of pressure fluid to the unloader valve S, a portion of pressure fluid will flow into the cylinder 18' of the relief valve 10 and will force the-piston l9-upwardly against the spring 20- to unseat the ball" valve 14. In this Way the pressure fluid utilized for opening the'valve 9 will beexhausted to the atmosphere and said valve q will then'be returned to its closed position by the springs u and g acting, against the piston s and the valve q respectively,

is,'as' long as the compressor remains idle and during the starting and stoppmgperio'ds:

Such being thecase, any" air" which may leak into the cylinder B Will be expelled therefrom through the check valves 4 and 5, the pipe 3 and thence through the ports 15 and 17 to the atmosphere. By permitting the Water valve 9 to close at the instant of unloading of the compressor, the supply of cooling water to the chambers of the Water jacket Will be immediately shut off. In this Way is effected. a considerable saving in the expense of operating the compressor. Thisis particularly advantageous in localities Where a free supply of cooling Water is not available and Where the cooling Water to the compressor is metered and paid for accordingly.

During the idle and starting periods of the compressor, the electro-magnet 80 will re main deenergized and consequently the auxiliary valve 23 Will occupy its open position to admit pressure fluid to the various unloading devices of the compressor, thus minimizing the starting load on the compressor motor. When the compressor approaches its maximum speed and the motor control switch is moved into position to admit full line current to the motor, the electro-magnet 30 will again become energized and allow the valve 23 to close and cut off communication between the pipes 24 and 25. The pressure fluid in the pipe 25 and the casing 33 Will then escape through the auxiliary valve 23 to the atmosphere in a Well known manner and permit the valve W to open under the influence of the spring X. At the same time the ball valve 14 Will return to its seat and cut off communication between the pipe 3 and the ports 17 The air discharged into the pipe 3 from the cylinder B Will then flow into the chamber a and, acting against the piston s, Will open the valve 9 to again admit Water into the Water jacket.

I claim:

1. In a compressor, the combination of a cylinder having inlet-and discharge openings, a receiver tank connected to receive pressure fluid discharged from the cylinder, a Water jacket on the cylinder, a Water valve, a pipe connected to the ends of the cylinder for conveying pressure fluid from the cylinder to the Water valve for holding said Water valve open during the operation of the compressor, and a relief valve interposed in the pipe adapted to remain closed during the normal operation of the compressor and actuated by receiver pressure for venting the cylinder and the Water valve to the atmosphere during the time the compressor is operating at less than normal speeds, thus preventing the compression of air leaking into the cylinder as Well as the flow of Water into the Water jacket.

2. In a compressor, the combination of a cylinder having inlet and discharge openings, a receiver tank connected to receive pressure fluid discharged from the cylinder, a water jacket on the cylinder, a Water valve, a pipe conveying pressure fluid from the ends of the cylinder to the Water valve for holding said Water valve open during the operation of the compressor, and a relief valve interposed in the pipe adapted to remain closed during the normal operation of the compressor and to be constantly held open by receiver pressure during the unloaded period of the compressor for venting the cylinder and the Water valve to the atmosphere, thus preventing the compression of air leaking into the cylinder and also preventing the flow of cooling Water into the Water jacket.

3. In a compressor, the combination of a cylinder having inlet and discharge openings, a receiver tank connected to receive the discharge from the cylinder, a water valve controlling the flow of Water into the Water j acket, a pipe connected to the ends of the cylinder to convey pressure fluid to the Water valve for holding said Water valve open duringthe operation of the compressor, and a relief valve interposed in the pipe adapted to remain normally closed and to be constantly held open by receiver pressure during the inoperative period of the compressor to prevent the compression of air leaking into the cylinder as Well as to prevent the flow of cooling Water into the Water jacket.

4. In a compressor, the combination of a cylinder having inlet and discharge openings, a receiver tank connected to receive the dis charge from the cylinder, a Water valve controlling the flow of Water into the Water jacket, a pipe connected to the ends of the cylinder to convey pressure fluid directly from the cylinder to the Water valve for holding said Water valve open during the operative period of the compressor, a relief valve interposed in the pipe and constantly held open by receiver pressure during the starting, stopping and idleperiods of the compressor to prevent the compression of air leaking into the cylinder as Well as to prevent the How of cooling Water into the Water jacket, and check valves in the pipe preventing the flow of air from the pipe into the ends of the cylinder during the time the relief valve is occupying its open position.

In testimony whereof I have signed this specification.

SNOVVDEN B. REDFIELD. 

